1. Field of the Invention
The invention relates to a power semiconductor module and to a method for manufacturing a power semiconductor module.
2. Description of the Related Art
In known power semiconductor modules, power semiconductor components, such as, for example, power semiconductor switches and diodes, are generally arranged on a substrate and electrically conductively connected to one another by means of a conductor layer of the substrate, and bonding wires and/or a foil composite. The power semiconductor switches are in this case generally in the form of transistors, such as, for example, IGBTs (insulated gate bipolar transistors) or MOSFETs (metal oxide semiconductor field effect transistors) or in the form of thyristors.
In this case, the power semiconductor components arranged on the substrate are often electrically connected to one another to form one or more so-called half-bridge circuits, which are used, for example, for rectifying and inverting electrical voltages and currents.
Conventional power semiconductor modules have DC voltage load connection elements for conducting load currents, with the aid of which DC voltage load connection elements the power semiconductor components are electrically conductively connected to the external environment. The load currents in this case generally have a high current intensity, in contrast to auxiliary currents which are used, for example, for actuating the power semiconductor switches. The DC voltage load connection elements generally need to be passed through the housing of the power semiconductor module. In this case, the demand is often made of power semiconductor modules to have protection from spray water (for example, to the level of IP54), for example, with the result that the DC voltage load connection elements need to be sealed off with respect to the housing. Since the DC voltage load connection elements generally need to be guided ideally parallel to one another and at a small distance from one another in order to realize a self-inductance which is as low as possible, sealing of the DC voltage load connection elements with respect to the housing is difficult to implement. In the case of conventional power semiconductor modules, the DC voltage load connection elements are injection-molded into the housing, which generally consists of a thermoplastic, or the interior of the power semiconductor module is cast by means of a casting compound after fitting of the power semiconductor module.
In conventional power semiconductor modules, the DC voltage load connection elements are cohesively connected to the housing in order to seal the DC voltage load connection elements with respect to the housing.
Conventional solutions for sealing the DC voltage load connection elements with respect to the housing in this case have only poor resistance to thermal cycling. Furthermore, the distance between the DC voltage load connection elements needs to be relatively large if the DC voltage load connection elements are intended to be injection-molded into the housing so that the thermoplastic can flow between the DC voltage load connection elements and the formation of meld lines extending between the DC voltage load connection elements is avoided.